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Social categorisation, distraction and intergroup discrimination.

Kakimoto, Toshikatsu (1994) Social categorisation, distraction and intergroup discrimination. Doctor of Philosophy (PhD) thesis, University of Kent. (doi:10.22024/UniKent/01.02.94450) (KAR id:94450)


This thesis reports an investigation of the phenomenon of intergroup discrimination and its underlying psychological processes, using cognitive distraction as a conceptual tool. It has been claimed theoretically that cognitive and motivational elements are both involved in intergroup discrimination. On the basis of social identity theory, it was pointed out that discrimination is based on the category differentiation process as a cognitive component and the social identity process as a motivational component. The category differentiation process is an accentuation mechanism of inter-class differences based on perceptual categorisation. The social identity process is a goal-oriented process to maintain and enhance ingroup-esteem by favourable intergroup comparison. It was further suggested that the category differentiation process is less intentional and more automatic than the social identity process.

By employing this qualitative difference, it was aimed to demonstrate empirically the distinct functioning of the two hypothetical processes. Namely, because distraction is thought to obstruct intentional processes in general, it was hypothesised that the social identity process would be hindered by distraction whereas the category differentiation process would be unaffected. However, it was proposed that the above proposition holds only when group membership is salient.

Three pilot studies and six "minimal group" experiments (involving 581,12-14 year olds) were conducted to examine these general propositions, using different operationalisations, measures, and procedures. In short, the hypotheses were generally supported with some modifications. For the social identity process, distraction was likely to reduce ingroup bias in point allocation, a form of intergroup discrimination in a minimal group situation. However, it was also found that the degree of distraction needs to be taken into account. Thus, it was proposed and demonstrated that noise from other intentions such as fairness and self-presentation, also interferes with the social identity process under no or weak distraction. As a result, intergroup discrimination in point allocation was strongest when moderate distraction eliminated noise from these other intentions, and weakest when strong distraction hindered the social identity process. For the category differentiation process, distraction hardly affected evaluative ratings and perceptual differentiation measured on new colour band scales. Theoretical and empirical implications are discussed.

Item Type: Thesis (Doctor of Philosophy (PhD))
DOI/Identification number: 10.22024/UniKent/01.02.94450
Additional information: This thesis has been digitised by EThOS, the British Library digitisation service, for purposes of preservation and dissemination. It was uploaded to KAR on 25 April 2022 in order to hold its content and record within University of Kent systems. It is available Open Access using a Creative Commons Attribution, Non-commercial, No Derivatives ( licence so that the thesis and its author, can benefit from opportunities for increased readership and citation. This was done in line with University of Kent policies ( If you feel that your rights are compromised by open access to this thesis, or if you would like more information about its availability, please contact us at and we will seriously consider your claim under the terms of our Take-Down Policy (
Uncontrolled keywords: Psychology
Subjects: B Philosophy. Psychology. Religion > BF Psychology
H Social Sciences > HM Sociology
Divisions: Divisions > Division of Human and Social Sciences > School of Psychology
SWORD Depositor: SWORD Copy
Depositing User: SWORD Copy
Date Deposited: 14 Jul 2023 08:49 UTC
Last Modified: 14 Jul 2023 08:49 UTC
Resource URI: (The current URI for this page, for reference purposes)

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